For conventional submarines, the battery in certain situations of application is the only source of energy. In order to be able to compute in advance the remaining travel duration which is possible, it is not sufficient to known the available energy quantity. On the contrary, the residual travel duration is rather dependent on several parameters. These are the battery operating parameters as well as the operating parameters of the remaining units of the submarine. The respective battery data are made available by a battery monitoring installation. For the remaining units of the submarine, calculated consumption values for common operating situations are specified by the shipyard, on the basis of which then with certain battery data the possible residual travel duration given a certain travel situation or the residual capacity of the battery remaining given a predefined travel duration may be determined by calculation.
The disadvantage with these known methods for determining the residual travel duration or remaining travel time of a submarine is the fact that the residual travel duration or the remaining residual capacity of a battery may only be determined relatively inaccurately.